Case Presentation • 22 yo U.S. Army Active Duty male deployed to Afghanistan west of Kandahar presents with fever (102.5o F), headache, fatigue, chills, abdominal pain with non-bloody diarrhea (SEP 8, 2009) • Symptoms progressing over the previous 4 days • Initially told he had a “gastroenteritis” at local clinic • Treated with Cipro and immodium • 48 hour quarters • Returned the following day (SEP 9): • Symptoms worsening, now with nausea/vomiting and lethargy • Told he may have a “viral syndrome” • Referred to Kandahar for observation
Case Presentation • Progressively worsened over the next several hours • Lethargy lead to somnolence • Bloody diarrhea and bleeding gums • Shortness of breath intubated • Anemic, low platelets, developing organ failure • Evacuated to LRMC with presumed diagnosis of pneumonia with septic shock (antibiotics started)
Case Presentation • Upon arrival at the Landstuhl Regional Medical Center, he is found to be bleeding EVERYWHERE • Petechiae everywhere • Large ecchymotic lesions at IV sites • Extremely sick • He requires emergent bronchoscopy for bleeding • The ICU staff raises the concern for viral hemorrhagic fever
Case Presentation • Co-located with Afghan army • Potential exposures • Numerous outdoor activities to include sleeping outside • Recent tick exposures • Patient and battle buddy both with recent bites within a week of illness onset • This was a common occurrence (bragging rights) • Exposure to goat blood and undercooked goat meat
Case Presentation • Blood sent to the Bernard Nocht Institute (BNI) in Hamburg within hours of admission • Blood run overnight • SEP 10: PCR and IGM POSITIVE for CCHF • Infectious diseases consulted just prior to test results • Within ~12 hours of diagnosis, treatment with oral ribavirin thru feeding tube • Dose given to match the standard IV dose • Emergency IND approval for IV ribavirin from the FDA • IV ribavirin started 12 hours after oral treatment (48 hours of hospitalization)
Case Presentation • Renal and hepatic dialysis started • Patient appeared to be improving • However: • SEP 14 • Patient had a asystolic/PEA arrests • Declared brain dead • At time of death, viral load had declined and antibodies present
Viral Hemorrhagic Fevers COL Art Lyons DCCS, DTHC Pentagon, Washington, DC
1995 Kikwit Zaire ZEBOV Outbreak Courtesy of Don Noah
Outline • VHFs in general • Epidemiology • Clinical aspects • Diagnosis • Preventive measures • Treatment
United State Army Medical Research Institute of Infectious Diseases (USAMRIID):
Potential of VHF’s for Weaponization • PRO • Many demonstrated as infectious by aerosol transmission • Exception is Dengue • Potentially high morbidity and mortality • Replicate well in cell culture • Exception are viruses in Bunyaviridae(e.g. CCHF) • Capability to overwhelm medical resources • Frightening effects of illness / terror value • CON • Lack of treatment or vaccine to protect user’s own “troops” • May not be deterrent for some countries / non-state actors • Possible entry into local vector / reservoir population • Stabilizers must be used to enhance viability
Other Military Relevance: History of Weaponization • Yellow fever and RVF were weaponized by the U.S. during their offensive program • Former Soviet Union produced large quantities of Ebola, Marburg, Lassa, Junin, and Machupo • Yellow fever may have been weaponized by North Koreans • The Aum Shinrikyo cult unsuccessfully tried to obtain Ebola virus to create biological weapons • Several studies have demonstrated ability to aerosolize Ebola, Marburg, Lassa, and some of the New World arenaviruses
Definition • Viral hemorrhagic fever (VHF): • Fever • Malaise • Myalgia prostration • Bleeding diathesis • Enveloped, single-stranded, RNA viruses • Hemorrhagic fever virus (HFV) is a term used to generically identify those agents that cause VHF.
Alkhurma Lujo Courtesy of Mike Bray, NIAID
Overview of Etiologic Agents of VHFs Family Genus Species FiloviridaeEbolavirus Zaire, Sudan, Ivory Coast, Reston, Bundibugyo Marburgvirus Lake Victoria marburgvirus ArenaviridaeArenavirusLassa, Lujo(“Old World”) Junin, Machupo, Guanarito, Sabia, (“New World”) BunyaviridaeNairovirus Crimean-Congo hemorrhagic fever Phlebovirus Rift Valley fever HantavirusHantaan, Seoul, Puumala, Dobrava, Sin Nombre FlaviviridaeFlavivirus Omsk HF Kyasanur forest disease (including Alkhurma) Dengue Yellow fever
Overview of Epidemiology of HFVs Natural Other Incubation Disease (virus) Distribution Host/ Sources (days) Vector Filoviruses Ebola HF Africa, Philippines (ER) Bats?Nosocomial 2-21 Marburg HF Africa Bats?Nosocomial 5-10 Arenaviruses Lassa fever and Lujo virus Africa Rodent Nosocomial 5-16 Argentine HF (Junin) South America Rodent Nosocomial 7-14 Bolivian HF (Machupo) South America Rodent Nosocomial 9-15 Venezuelan HF (Guanarito) South America Rodent Nosocomial 7-14 Brazilian HF (Sabia) South America Rodent Nosocomial 7-14 Bunyaviruses CCHF Europe, Asia, Africa Tick Animal slaughter, Nos. 3-12 Rift Valley fever Africa Mosquito Animal slaughter 2-6 HFRS/HPS (Bunyaviridae) World-wide Rodent 9-35 Flaviviruses Omsk HF Soviet Union Tick 2-9 Kyasanur forest disease India Tick 2-9 Dengue HF Asia, Americas, Africa Mosquito 3-15 Yellow fever Africa, tropical America Mosquito 3-6 Alkhumra HF Saudi Arabia, Egypt Tick 2-9
How are VHFs Spread? 1 – Inhaling or ingesting excretions/secretions from rodent hosts (urine, feces) 2 - Bite of an infected arthropod (tick, mosquito) 3 – Nosocomial/lab transmission – contact with human or animal blood/body fluids/tissue 4 - Artificially generated aerosols (biowarfare)
How are VHFs spread? • In NHPs – possible airborne transmission between cages 3 meters apart • Lung tissue with documented virus • In NHPs and GPs: infective via airborne, conjunctival, oral exposure • Viremia – 3-5 days • 1 day prior or simultaneous with clinical illness (D4-5) • Virus recovered from nares, pharynx, conjunctivae, anus (days 7-10; limited numbers) Arch Pathol Lab Med 1996;120: 140-5. Int J Exp Path 1995;76:227-36. Lancet 1995;346:1669-71. Arch Virol 1996(suppl);11:115-134.
VHF Human-to-human transmission • Only dengue and yellow fever virus have adapted to efficient human-to-human transmission (via mosquitoes). • For other HF viruses, humans are “dead-end” hosts. • Typical story for nosocomial transmission: • Uncertain how first human/NHP is infected • Patient enters the health care facility • VHF is not recognized or infection control procedures are not followed • Unrecognized nosocomial spread from blood/body fluid contact • Health care personnel among the victims • Victims carry infection to the community • Close family members and those doing burial rites facilitate further spread • No proven human to human respiratory transmission
How are VHFs Spread Person to Person? • Usually spread during patient care without appropriate barrier precautions • Contact with blood/tissue/body fluids • Includes re-use of syringes/needles • Epidemiologically, VHFs not readily transmitted person-to-person by airborne route • A possibility in only rare circumstances • Highest risk in later stages, when having vomiting, diarrhea, shock, hemorrhage • Not reported during incubation period (before fever) MMWR 1995;44(25):475-79.
Model of Filoviral Pathogenesis in Primates 1 4 3 5 2 6
VHF: Spectrum of Clinical Presentations • Variety of presentations • Prodrome • High fever, Headache, Malaise, Arthralgias, Myalgias • Nausea, Abdominal pain, Non-bloody diarrhea • Early signs • Fever, Tachycardia, Tachypnea, Conjunctivitis, Pharyngitis • Flushing, Skin Rash • Late • ↓ BP, Hemorrhagic diathesis, Petechiae, Mucous membrane • Conj. hemorrhage, Hematuria, Hematemesis, Melena • Major Manifestations • DIC, Circulatory Shock, CNS dysfunction
Argentine Hemorrhagic Fever (Junin virus – New World Arenavirus ) Gingival hemorrhage
Bolivian Hemorrhagic Fever(Machupo virus – New World Arenavirus) Conjunctival injection & subconjunctival hemorrhage Ref: Current Science/Current Medicine (Peters CJ, Zaki SR, Rollin PE). Viral hemorrhagic fevers. In: Fekety R, vol ed. Atlas of Infectious Diseases, p10.1-10.26, Volume VIII, 1997.
CCHF Left arm. Ecchymosis, diffuse, severe. (1 week after clinical onset) Photo credit: Robert Swaneopoel, PhD, DTVM, MRCVS, National Institute of Virology, Sandringham, South Africa.